PRECAST concrete solutions

The concrete industry is facing growing challenges due to the depletion of natural resources caused by increased construction activity. One of the most pressing issues is the scarcity of natural aggregates used in concrete mixes. To maintain production levels that meet societal demands, concrete producers—including those in the precast sector—must explore alternative raw materials.

Mapei’s RE-CON line offers a comprehensive approach to promoting a more sustainable concrete lifecycle. Within this line, the Re-Con AGG range leverages advanced admixture technology to enable the use of challenging aggregates such as:

• Manufactured sands with high fines content and possible presence of free mica minerals,
• Sands with clay intrusions,
• Recycled Concrete Aggregates (RCA) containing residual calcium compounds.

According to estimates, returned concrete accounts for around 3% of the total amount produced, or around 900 million tonnes per year at a global level. Returned concrete leads to high environmental impact and the need for disposal. Today, with Re-Con Zero EVO Mapei makes it is possible to recover and transform returned concrete, thereby going from a linear economic model, based on the production of waste, to a more circular economic model.
Re-Con Zero EVO is used to reduce the waste generated by the concrete production processes by transforming returned concrete into aggregate that can be used in the production of new concrete.

Sealants for moulds play a crucial role in precast production by ensuring dimensional precision, high-quality surface finishes, and effective leak prevention. These products are specifically formulated to seal joints, interfaces, and gaps between mould components preserving the integrity of the mould cavity, minimizing surface defects, and extending mould service life.

• Mapesil Z
  A high-elasticity, acetoxy silicone sealant that guarantees long-lasting watertightness. It offers excellent adhesion to a wide range of substrates (steel, wood, and composites) and excellent resistance to weathering, deformation, and resistance to alkaline materials.
• Mapepur Universal Foam
  A range of versatile polyurethane-based foams, available for both hand-held and gun applications, combining strong mechanical resistance with excellent filling and bonding capabilities. Ideal for sealing joints and movable parts exposed to casting pressure.

• Leak Prevention: Securely seals mold joints, preventing slurry and water escape during casting.
• Dimensional Integrity: Maintains precise geometries under pressure.
• Defect Reduction: Minimize blowholes and irregular edges
• Mould Protection: Prevent cement intrusion into mechanical joints, reducing wear
• Productivity Gains: : Less rework, fewer interruptions, and optimized cycle times

• Steel molds for structural elements (beams, slabs, columns)
• Battery molds and tilting tables for architectural panels
• Adjustable moulds with moving or pressurized parts
• Wood or composite moulds for custom or small-batch production
• Modular and automatized production lines

One of the most crucial stages in precast concrete manufacturing is the demoulding phase. Releasing concrete elements from the formwork must occur within a controlled and minimized timeframe to maintain structural integrity and avoid surface defects.

Mapeform form-release agents are specifically designed to ensure clean, effortless demoulding while protecting the integrity of the mould. Available in both water-based and vegetable oil-based formulations, they deliver excellent surface quality, reduce imperfections, and help extend the lifespan of production equipment by minimizing maintenance needs.

Key benefits:

• Ensure easy and clean demoulding
• Preserve formwork surfaces and extend reuse cycles
• Minimize air voids and improve surface finish
• Available in water-based and vegetable oil-based formulations

Fiber reinforced concrete is one of the most promising technologies in the precast industry. Structural synthetic macrofibers are tridimensional reinforcement systems designed to improve post-crack behaviour, impact resistance, and fatigue performance of concrete. They offer a corrosion-free alternative reinforcement in various structural applications, thereby enhancing the sustainability of the precast industry.

Mapei is a global leader in the engineering and manufacture of high-performance macro synthetic fiber-based reinforcement systems for concrete. As a comprehensive solutions provider, Mapei offers advanced technical support for the design and formulation of fiber reinforced concrete.

Besides, the company also offers micro fibers that improve the resistance of concrete to cracks caused by plastic shrinkage, which guarantees an easy dispersion and distribution within the concrete matrix.

Key benefits of fibers:

• Ensure post-crack tensile and flexural strength
• Improve impact resistance and fatigue performance
• Allow reduction or replacement of traditional steel reinforcement
• Simplify logistics and increase safety on-site

The Planitop Rasa&Ripara Zero range includes high-performance cementitious and polymer-modified mortars specifically formulated to restore the appearance, durability, and structural integrity of damaged or defective concrete elements.

Ideal for vertical, overhead, and horizontal applications, Planitop Rasa&Ripara Zero range mortars deliver excellent adhesion, workability, and mechanical strength, making them the ideal choice for efficient and long-lasting repairs.

Key benefits:

• Fast setting and drying in all seasons
• Speeds up repair work
• Durability
• Hardens without cracking
• For repair and skim coating applications
• Thickness range: from 3 mm to 40 mm
• Excellent workability and thixotropy
• Smooth, uniform finish
• CO₂ emissions fully offset

The application of elastomeric paints and coatings from the Elastocolor range creates an effective barrier for concrete surfaces, protecting them from carbonation and significantly reducing the development of cracks and micro-cracks.

The finishes of the Elastocolor range form a continuous, elastic layer that adapts to the movements of the substrate, thus reducing the risk of deterioration even in the presence of thermal or mechanical stress. They effectively inhibit the penetration of aggressive atmospheric agents such as carbon dioxide (CO₂) and sulphur dioxide (SO₂), which accelerate the deterioration of reinforced concrete. They therefore make a concrete contribution to extending the life cycle and durability of concrete. Furthermore, the finishes in the Elastocolor range can be produced in an unlimited number of colours, combining aesthetic appeal with technical performance.

In addition to the Elastocolor range, Mapei offers Colorite Beton and Colorite Performance: anti-carbonation acrylic paints, ideal for protecting and decorating concrete elements. Colorite Beton is a semi-transparent paint that protects the substrate and gives it a uniform colour without hiding the surface appearance of the structures. Colorite Performance gives concrete elements an attractive finish and can be coloured even in the most intense and bright shades.

The Elastocolor and Colorite coatings feature high resistance to climatic aggression, CO₂ penetration and carbonation. They are available in a wide range of colours and comply with European Standard EN 1504-2 (“Surface protection systems for concrete”).

Mapei developed the Mapefill ranges of grouts to anchor concrete elements and filling voids under structural baseplates. Thanks to their high-flow, excellent mechanical strength, and superior dimensional stability, they ensure secure, durable load transfer in both dynamic and static conditions.

Key benefits:

• Fill voids under baseplates
• Anchor steel and concrete elements
• High mechanical strength at early and final stages
• Shrinkage-compensated to ensure excellent adhesion
• >Resistant to both static and dynamic stress

Elastic sealants prevent the ingress of atmospheric agents and guarantee thermal and acoustic insulation of construction and expansion joints, even those subject to joint movements.

Mapei offers a complete range of solutions to meet all sealing and bonding requirements. Some products in the Mapeflex range are specifically designed for sealing joints in precast elements.

To guarantee the designed durability of the structure, pre-cast concrete elements must be properly waterproofed and protected against water, moisture and weathering/chemicals, according to the specific field of application where they will be used.

In below-grade applications, surface sealing and protection can be achieved using a fully bonded, highly flexible sheet membrane choosing from:

• pre-applied membranes, such as Mapeproof FBT, which are applied in the formworks in the manufacturing plant before applying reinforcement and concrete, and only the joints are sealed on site using the Mapeband Flex Roll system.
• a post-applied membrane such as Mapeproof SA which is applied on the precast element once it has been casted on site.

Dry-mix concrete is one the most relevant solutions for manufacturing high-quality precast elements such as blocks, pavers, and pipes. Its low water content allows for rapid demoulding, excellent dimensional control, and high mechanical strength at early stage.

Thanks to the Vibromix range of concrete admixtures, the efficiency of the production process is significantly enhanced through advanced vibration and compaction technology. The resulting concrete elements are highly durable and uniform.

The use of Vibromix products helps address key challenges in dry-mix concrete production — including moisture control, mix precision, and equipment performance — enabling greater process stability and overall optimization.